Feank bhind



(No Model.)

P. RHIND.

GENTRAL DRAFT LAMP AND BURNER. No. 382,270. r Patented May 1, 1888.

W/T/VESSES: v ,l/VI/E/l/TOR. ;d I. BY

- Arron/mt UNITED STATES PATENT l EErcE.

FRANK RHIND, OF MERIDEN, CONNECTICUT, ASSIGNOR OF ONE-HALF TO CHARLESSTANFORD'UPTON, OF NEl/V YORK, N.'Y.

CENTRAL-DRAFT LAMP AND BURNER.

SPECIFICATION forming part of Letters PatentNo. 382,270, dated May 1,1888.

Application filed December 20, 1886. Serial No.22-2J25. (No model.)Patented in England January 12, 1887, No. 500; in Belgium January 17,1887, No. 75,981, and in France JanuarylS, 1887, No. 180,986.

' To aZZ whom it may concern:

Be it known that I, FRANK RHIND, a citizen of the United States,residing at Meriden, in the county of New Haven and State of Comneetieut, have invented certain new and useful Improvements inCentral-Draft Lamp-Burners, of which the following is a specification.

In that class of central-draft lamp-burners of which the Rochester andthe Niagara lamps are types the central tube which supplies air to theinside of the flame is surmounted by a cone or thimble having animperforate top, but having its sides covered with small perforations,which distribute the air to the flame. In those lamps which, like theRochester, have the central-draft tube extending down entirely throughthe fount, the increased length of the draft thus provided renders thesupply of air to the flame so steady that a single cone or thimble atthe top of the tube, when properly perforated, will distribute the airsteadily to all parts of the flame, so that the latter will not flicker;but where, as in the Niagara lamp, the central-draft tube is in theburner only, an ordinary fount or reservoir being used, there is notsufficient length of tube to give steadiness to the draft, and I havefound that where in such a lamp but a single perforated cone or thimbleis employed at the top of the tube the flame is liable to suchflickering as to materially injure the value of the lamp. To remedy thisdefect I have attempted to steady the draft by lessening the area of theinlet-openings at the base of the tube; but an improvement was noteffected, probably for the reason that the air, when once within thetube, was allowed to rush, without interruption, to the perforated coneor thimble, and thus to the flame. I have found, however, that byplacing at the top of the tube, within the cone or thimble, a secondcone or thimble suitably perforated the direct rush of air to the outercone is so interrupted as to destroy the eddies and render the flamealmost perfectly steady. The space inclosed between the two cones orthimbles serves as a heating-chamber for the air, and the heating actionis increased by reason of the fact that,

owing to the expansion of the air which takes place in this chamber, theflow of air through the inner cone or thimble is slower than the flowthrough the outer cone or thimble. This heating action may be increasedbyincreasing the number of cones, several concentric chambers being thusprovided, through which'the air passes outwardly, gaining in bulk by expansion as it nears the flame. To facilitate the flow of air, as well asto prevent the arrest of material by the inner cone or cones or thimbleor thimbles after passing through the outer cone or thimble, theperforations in the latter are preferably somewhat larger in area thanin the former.

My invention Will first be described with reference to the accompanyingdrawings, and then pointed. out in the claims.

In said drawings, Figure 1 is a vertical sectional view of a Niagaralamp-burner embodying my invention. Fig.2 is a sectional view of a coneor thimble of cylindrical form. Figs. 3' and 4 are similar viewsillustrating other forms of cones 0r thimblcs.

A is the case or shell of the burner, having near the base, at A,perforations sufficient in area to supply air freely to the inner tube,B, which, in connection with the outer tube, B, forms an annularwickspace. The wick is carried by the rings C O, and operated incustomary manner by the wick-rod P. At top of and fitting the tube B isa cone or thimble, F, which is slightly conical, as shown in Figs. 1, 2,and 4:, or cylindrical, as shown in Fig. 2. In the former case the coneis surmounted by a head, F, having its under sides perforated, like theremainder of the cone or thimble below it. This head may vary somewhatin size and form, as shown in the figures. In each case the top of thecone or thimble is imperforate, so that air within the same is directedlaterally through its sides.

Where but a single cone, F, is employed, it 0 is found that the airrushing directly to the flame will be so unsteady and filled with eddiesas to cause the flame to flicker. This difficulty is, as already pointedout, obviated by me by placing within the cone F a second cone orthimble, G, which may be of such diameter at its lower end as to bear onthe inside of the outer cone, F, and which is preferably made with alarge number of perforations, which are somewhat larger in area than theperforations in the outer cone, for the purpose already set forth. Notonly is the air steadied by reason of this inner cone preventing the airfrom rushing directly through the perforations of the outer cone, but astill-air chamber is provided between the cones F and G, and within thischamber the air is heated and expanded, and then supplied steadily tothe flame throughout the whole lateral surface of the outer cone orthimble.

It will be seen that the air-chamber inclosed between the two conesissurrounded by the flame, to which it supplies air, so that the air inthis chamber is directly heated by the It is not intended to claimanything in this application which is claimed in mycontemporaneousapplication, Serial N 0. 242,569.

Having thus described my invention, the following is what I claim as newtherein and desire to secure by Letters Patent:

1. In combination with a burner having a central-draft tube and aperforated cone or thimble at the top of said tube, a second perforatedcone or thimble within the first, whereby an air-chamber is providedbetween the two cones, substantially as and for the purpose set forth.

2. In a burner having a central air tube,

the combination, with a cone or thimble at the top of said tube havingan imperforate top and perforated sides; of a second cone or thimblewithin the first, having its sides perforated to supply air to thechamber between the two cones, substantially as and for the purpose setforth.

- 3. In a burner having a central air-tube, in combination with a coneor thimble at the top of said tube, perforated substantially as setforth, a second cone or thimble within the first and removabletherefrom, and also perforated, substantially as set forth.

4. In combination with a burner having a central air-tube, a perforatedcone or thimble I fitting the upper end of the central air-tube, and aninner cone or thimble fitting inside the first cone or thimble,substantially as shown and described.

5. In a burner having a central air-tube, the combination, with a coneorthimble at the top of said air-tube having its sides perforated,

for the purpose set forth, of a second cone or thimble within the first,and having in its sides perforations larger than those in the first coneor thimble, substantially as and for the purposes set forth.

FRANK RHIND.

Witnesses:

HERBERT KNIGHT, CHAs. S. UPToN.

